Starling 2 GPS Count

kestrelsystemsbp · 7 Mar 2025, 07:37

Are there any procedures one needs to initiate in order to get the GPS working? Because I constantly have a GPS Count of 0, and I have tried looking around on the internet to find any tips about it.

Alex Kushleyev · 9 Apr 2025, 03:06

Hi @kestrelsystemsbp , the GPS interference is an ongoing investigation and there are several threads about this on the forum. For Starling 2, we found that moving the wifi dongle to a different location (or offsetting the GPS receiver) helps with interference (it is located right under the gps receiver). Also, elevating the gps receiver and shielding, should help. Please also read through the following discussion related to Starling 2 Max : https://forum.modalai.com/topic/4226/starling-2-max-no-gps-data/

I am not saying that you need such a big mast, but you may need to experiment a bit to figure out how to improve.

I am sorry for the inconvenience and let me know if you need any guidance for checking the signal strength, as described in the other thread. You do not have to use the live streaming plot for checking the individual signal strength -- you could do it directly using the terminal.

enable satellite info to be published from px4 (and start voxl-px4)

param set GPS_SAT_INFO 1

query satellite info using px4-listener:

px4-listener satellite_info

TOPIC: satellite_info
 satellite_info
    timestamp: 2611309684 (0.868903 seconds ago)
    count: 13
    svid: [5, 8, 10, 13, 15, 18, 23, 24, 27, 32, 131, 133, 138, 0, 0, 0, 0, 0, 0, 0]
    used: [1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0]
    elevation: [11, 1, 30, 11, 47, 64, 68, 59, 13, 15, 27, 19, 33, 0, 0, 0, 0, 0, 0, 0]
    azimuth: [74, 232, 213, 36, 37, 138, 241, 85, 209, 172, 165, 173, 158, 0, 0, 0, 0, 0, 0, 0]
    snr: [0, 0, 26, 17, 32, 14, 29, 30, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
    prn: [5, 8, 10, 13, 15, 18, 23, 24, 27, 32, 131, 133, 138, 0, 0, 0, 0, 0, 0, 0]

In open sky conditions, you should have a number of satellites above 40dB (which is not the case in this example i just pasted above). You can see the examples of the good and bad signal in the Starling 2 MAX thread i mentioned above.

Alex